package com.changgou.system.filter;

import com.changgou.system.util.JwtUtil;
import io.jsonwebtoken.Claims;
import org.apache.commons.lang.StringUtils;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

/**
 * 过滤器:用于token验证
 */
@Component
public class AuthorizeFilter implements GlobalFilter, Ordered {
  @Override
  public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
    //1. 获取请求        
    ServerHttpRequest request = exchange.getRequest();
    //2. 则获取响应
    ServerHttpResponse response = exchange.getResponse();
    //3. 如果是登录请求则放行
    if (request.getURI().getPath().contains("/admin/login")) {
      return chain.filter(exchange);
    }
    //4. 获取请求头
    HttpHeaders headers = request.getHeaders();
    //5. 请求头中获取令牌
    String token = headers.getFirst("token");
    if (StringUtils.isEmpty(token)) {
      //如不存在,响应回错误信息.HttpStatus.UNAUTHORIZED:表示当前用户认证失败
      response.setStatusCode(HttpStatus.UNAUTHORIZED);
      return response.setComplete();//返回
    }
    //9. 如果请求头中有令牌则解析令牌
    try {
      Claims claims = JwtUtil.parseJWT(token);

    } catch (Exception e) {
      e.printStackTrace();
      //10. 解析jwt令牌出错, 说明令牌过期或者伪造等不合法情况出现
      response.setStatusCode(HttpStatus.UNAUTHORIZED);
      //11. 返回
      return response.setComplete();
    }
    //12.放行
    return chain.filter(exchange);
  }

  @Override
  public int getOrder() {
    return 0;
  }
}
